Al-Qayyūm
As for the name ‘the All-Sustainer’
He is the All-Sustainer, the One Who does not need any of His creation; and He is sustaining all those in the heavens and earth who all stand in need of Him.

This noble name occurs 3 times in the Qur’an, most notably in the Verse of Al-Kursi: (Allah - there is no god except Him, the Ever-Living, the All-Sustainer.) (Sūrat AlBaqarah: 255) And also in the initial verses in Sūrat Āl-‘Imrān: (Alif, Lam, Meem. Allah - there is no god except Him, the Ever-Living, the All-Sustainer.) (Sūrat Āl-‘Imrān: 1-2)

In light of these two great names, I would say:
1. Always remember that the Greatest One who deserves praise and loves to be praised is Allah Almighty. His name ‘the All-Sustainer’ is coupled with the name the Ever-Living to comprise all the attributes of absolute perfection, complete self-sufficiency and absolute power.

2. Stand in need of your Lord constantly. You are innately needy and He is innately Self-Sufficient. Remember that the more you feel humble and needy before your Lord, the richer you become.

3. Know that your life and movements entirely depend on Allah, the Sustainer. So, reform your relationship with Him so that He will give you good health and guide your steps.
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4. Stick to invoking Allah Almighty using His names ‘the Ever-Living’ and ‘the All-Sustainer’ for it is reported in the Hadīths that this helps get your invocation answered and your need fulfilled. In a Hadīth reported by Anas, a man supplicated to Allah Almighty using these two great names and praising Him. Thereupon, the Prophet (may Allah’s peace and blessings be upon him) said, “He invoked Allah by His greatest name by which when asked, He gives, and by which when supplicated, He answers.”35
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35 Narrated by Al-Nasā’i)
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